# Protein shakes for weight loss: do they help? Canonical URL: https://www.hemed.com/blog/protein-shakes-for-weight-loss Plain-text URL: https://www.hemed.com/blog/protein-shakes-for-weight-loss/llms.txt Published: 2026-10-14 Modified: 2026-10-14 Author: The HeMed clinical team Topic: Living well Topic URL: https://www.hemed.com/blog/topic/living-well Tags: Protein, Nutrition Reading time: 15 min Publisher: HeMed (https://www.hemed.com/) ## Summary Do protein shakes help with weight loss? What the trials and dietitians say, how NICE describes meal replacements, and how to read a shake label. ## Article A protein shake is a protein source, not a weight-loss method. The British Dietetic Association (BDA) says a healthy, balanced diet should provide enough protein in most cases. That includes people who train. Supplements "will not compensate for poor food choices but may be helpful in certain situations". The trial evidence is modest. Across nine randomised trials in adults who were overweight or obese, whey supplementation gave slightly more weight loss than control. The difference was 0.56, with no unit stated in the abstract. That is a population statistic, not a prediction for you. This article sets out what UK dietitians, the trials and the food rules say about shakes. It covers where the evidence stops and when food is the better choice. ### What is a protein shake and how much protein does it carry? A protein shake is a drink made from protein powder mixed with water or milk, or sold ready to drink. Whey is a protein from milk. Plant powders use protein from sources such as soya or pea. The Food Standards Agency (FSA) lists protein powders among "sports/fitness supplements". Food supplements "are not intended to replace a varied and balanced diet". How much protein a shake carries depends on the product. CoFID (the UK government's food composition dataset) has no entry for whey or any protein powder. So this article quotes no typical value; the figure on the pack is the only reliable one. #### What can a shake label claim? "Only authorised claims in the Great Britain NHC register may be used in Great Britain." NHC stands for nutrition and health claims. The register authorises three health claims for protein: - "Protein contributes to a growth in muscle mass" - "Protein contributes to the maintenance of muscle mass" - "Protein contributes to the maintenance of normal bones" Each applies only to a food that is at least a "source of protein" as defined in the Annex to the retained Regulation 1924/2006. No authorised protein claim mentions fullness or weight. A claim that protein-rich foods help you "feel you satiate longer" was refused for that food because the effect "has not been substantiated". ### Do protein shakes help you lose weight? Only inside an energy deficit, and then by a small margin in trials. The National Institute for Health and Care Excellence (NICE) says any dietary approach for weight management must keep total energy intake below energy expenditure. A shake added on top of your usual food adds energy. #### What did the trials find? Wirunsawanya and colleagues pooled nine randomised controlled trials (RCTs) of whey against placebo (an inactive comparison) or control in adults who were overweight or obese. An RCT assigns people to groups at random. A placebo is an inactive comparison. The whey groups lost 0.56 more body weight and 1.12 more fat mass than the comparison groups. The abstract gives these figures without stating a unit. The authors called for further studies on how much whey to take and for how long. Miller and colleagues pooled 14 RCTs with 626 completers, in generally healthy adults. When whey replaced other calories, body weight fell by 4.20 kg from baseline and body fat by 3.74 kg. The 95% confidence interval for weight was 0.73 to 7.67 kg, the range the true average is likely to sit in. #### What is the difference between within-group and between-group results? Those 4.20 kg are a within-group result: change from the start in one group, with no comparison. It cannot tell you what the whey itself added. A between-group figure compares the whey group with a comparison group. In Miller's between-group analyses whey looked more favourable against carbohydrate than against other proteins. The "findings did not reach statistical significance", meaning they could be chance. Lean mass is muscle and other non-fat tissue. Miller found a 2.24 kg gain in lean body mass among studies that paired whey with resistance exercise, meaning working muscles against a load. Average trial results are not a prediction of individual results. Both reviews were read at abstract level, and Miller's authors worked at a scientific consultancy. ### Are shakes as filling as food? The evidence does not settle this. Satiety is the fullness that ends a meal and delays the next one. A 2003 review reported that liquids "fail to trigger physiological satiety mechanisms", so compensation for energy drunk "may be imprecise and incomplete". The same review called the evidence "inconclusive". Some studies found liquids less satiating than solids; others found the reverse. A 2013 systematic review pooled 48 publications and 253 preload tests: 121 liquid, 69 semisolid, 20 solid and 43 mixed. A preload is a set food or drink given before a meal, to measure how much less people then eat. Energy compensation ranged from minus 370% to 450%. Minus means overconsumption, "mostly of liquids". Compensation was greatest when the preload was semisolid or solid and the next meal came 30 to 120 minutes later. Protein itself has a "modest satiety effect" and the evidence "does not support an effect on energy intake at the next eating occasion". A shake can count towards your protein without making you eat less later. ### What is the difference between a protein shake and a meal replacement? A protein powder is a food supplement. A meal replacement is a product built to replace a whole meal under set rules. The rules sit in the retained Regulation (EU) 432/2012. kcal means kilocalories, the energy unit on UK food labels. Condition | What the Regulation requires of a meal replacement Energy | Not less than 200 kcal and not more than 250 kcal per meal Fat | Not more than 30% of the product's total energy Protein | Not less than 25% and not more than 50% of the product's total energy Vitamins and minerals | At least 30% of the nutrient reference values per meal Label information | The importance of adequate daily fluid intake, and that the product works only as part of an energy-restricted diet with other foods #### Which meal-replacement claims are authorised? Two, both in the GB register: - "Substituting two daily meals of an energy restricted diet with meal replacements contributes to weight loss" - "Substituting one daily meal of an energy restricted diet with a meal replacement contributes to the maintenance of weight after weight loss" Both apply only to products that meet the conditions above, used inside an energy-restricted diet. A protein powder sold as a food supplement is a different product. Unless it meets every condition, it cannot carry these claims. ### What does NICE say about meal replacement and total diet replacement? NICE describes meal replacements as part of specialist-service programmes, not as something to start on your own. Its guideline NG246 covers low-energy diets of 800 to 1,200 kcal a day and very-low-energy diets under 800 kcal a day. In the evidence NICE reviewed, these diets were total or partial meal replacement. NICE says to consider low-energy diets "only as part of a multicomponent overweight and obesity management strategy" within "a specialist overweight and obesity management service". Very-low-energy diets are for people with "a clinically assessed need to lose weight rapidly", such as before surgery. Neither is a long-term strategy. #### What must these diets include? - nutritionally complete formulation - a limit of 12 weeks - ongoing clinical support, with access to a registered dietitian or registered nutritionist - advice on reintroducing a wider range of foods NICE also asks services to explain the risks: weight cycling, weight regain and adverse events. Very-low-energy diets add constipation, fatigue and hair loss. Separately, it advises against restrictive diets that are nutritionally unbalanced. They are "ineffective in the long term and can be harmful". #### What did a UK trial of total diet replacement find? The DROPLET trial ran in 10 GP practices in Oxfordshire with 278 adults who were obese and seeking support to lose weight. Formula food products provided 810 kcal a day as the sole food for the first eight weeks. Participants had weekly behavioural support for 12 weeks, then monthly support for three months. At 12 months the total diet replacement group had lost 10.7 kg, against 3.1 kg with usual care. The adjusted difference was 7.2 kg (95% confidence interval 4.9 to 9.4 kg). In the diet group 45% lost 10% or more of their weight, against 15%. Adverse events of moderate or greater severity affected 11% and 12%. These are population statistics from a supervised programme. The trial was part funded by a meal-replacement manufacturer; the authors state they received no personal financial benefit. ### How do you read a shake label? Read the protein per serving, the energy per serving and the sugars per 100 g or 100 ml. The NHS gives per 100 g thresholds for high and low. Department of Health front-of-pack guidance gives separate thresholds for drinks per 100 ml. The guidance's first question is "Is it a food or drink product?" A powder labelled per 100 g as sold falls under the food thresholds. A ready-to-drink shake falls under the drink thresholds. #### What counts as high and low? Nutrient | Food, per 100 g: low / high | Drink, per 100 ml: low / high Total sugars | 5 g or less / more than 22.5 g | 2.5 g or less / more than 11.25 g Fat | 3 g or less / more than 17.5 g | 1.5 g or less / more than 8.75 g Saturated fat | 1.5 g or less / more than 5 g | 0.75 g or less / more than 2.5 g Salt is high at more than 1.5 g per 100 g and low at 0.3 g or less. On a traffic-light label red means high, amber medium and green low. The NHS says to limit anything with a red. Front-of-pack labelling is voluntary. #### Which three things should you check? - Protein per serving, as the label states it. CoFID gives no reference figure, so the pack is the source. - Energy per serving in kcal, and whether the shake adds to or replaces food you already eat. - Any claim on the pack. Only claims authorised in the GB register are permitted. ### When is food the better choice? In most cases. The BDA says that "providing energy requirements are met, a healthy, balanced diet should provide enough protein to meet any increased requirements". Its supplements sheet adds that "there is no supplement that provides the same nutritional benefits of a healthy balanced diet". Most men already eat more protein than the minimum. The reference nutrient intake (the daily amount that covers nearly everyone's needs) is 0.75 g per kg of body weight. For men aged 19 to 64 that is 55.5 g a day. Average UK men of that age eat about 87 g a day, or 1.04 g/kg. The weight-loss research points higher. A 2015 review concluded that 1.2 to 1.6 g/kg a day improved appetite and weight management, with about 25 to 30 g per meal. Protein calculator Enter your weight and see the trial range, a per-meal split and the UK reference intake. Work out your protein range For an 85 kg man that is about 102 to 136 g a day. Our guide to how much protein you need to lose weight works through the sums. #### What does a portion of food give you? The table uses CoFID 2021 values and British Nutrition Foundation (BNF) portion sizes. Each protein figure is computed from the two and rounded, so each is "about". Food | Portion | Protein | Energy Chicken breast, grilled, skinless | 120 g | about 38 g | about 178 kcal Tuna, canned in brine, drained | 120 g, a medium can | about 30 g | about 131 kcal Eggs, boiled | 2 eggs, 120 g | about 17 g | about 172 kcal Lentils, red split, boiled | 120 g, about 6 tablespoons | about 10 g | about 122 kcal A protein shake | one serving | as the label states | as the label states Food brings more than protein. The NHS describes meat as a source of iron, zinc and B vitamins. It describes pulses as low in fat and high in fibre. NHS weight-loss advice is to "include some protein in each meal" from beans, pulses, fish, eggs or lean meat. The full list is in our UK list of high-protein foods for weight loss. If you are considering a supplement, the BDA says to "consult a registered practitioner" first. ### What does the evidence say about protein and your kidneys? For adults without kidney disease, higher protein intakes did not change kidney function in trials. A 2018 meta-analysis (a study that combines several trials into one estimate) pooled 28 trials with 1,358 participants. It compared high-protein intakes (1.5 g/kg or more, or 100 g a day or more) with normal or lower intakes. Glomerular filtration rate measures how well the kidneys filter blood. Its change did not differ between groups, though most of the trials were short. Kidney disease changes the picture. An NHS trust leaflet on chronic kidney disease advises meeting protein goals through normal diet "without supplementation such as protein shakes or protein powders". That is a local trust leaflet rather than national guidance; if you have kidney disease, ask your GP or dietitian first. The FSA adds a supply caution: buy food supplements online only from a business you are confident is reputable, and "beware of counterfeit products". ### Frequently asked questions **Are protein shakes bad for your kidneys?** In adults without kidney disease, a meta-analysis of 28 trials with 1,358 participants found no difference in kidney filtration between higher and lower protein intakes. Most of those trials were short. If you have chronic kidney disease the advice differs. An NHS trust leaflet says to meet protein goals through normal diet without shakes or powders. Ask your GP or dietitian for your own target. **Can you have a protein shake every day?** No source in this article gives a safe or useful frequency, so we do not state one. The authors of the 2018 whey review asked for more work on how much and for how long. The FSA says food supplements are not intended to replace a varied and balanced diet. The BDA says food first. A daily shake is a daily decision about what it replaces. **Is whey or plant protein better for weight loss?** The evidence does not separate them. In the 2014 meta-analysis, whey compared with protein sources other than whey did not reach statistical significance. No trial in this article tested a plant powder on its own for weight loss. **Do protein shakes build muscle without training?** The 2014 meta-analysis found a 2.24 kg gain in lean body mass only in studies that combined whey with resistance exercise. It reports the lean-mass gain only for that group of studies. The BDA says muscle gain needs resistance training with enough energy and about 1.6 to 1.7 g of protein per kg a day. The protein can come from food. **Is a protein shake a food supplement?** A protein powder is. The Food Standards Agency lists protein powders among sports and fitness supplements, which are not intended to replace a varied and balanced diet. They must not be sold with claims that they prevent, treat or cure anything. **How much sugar is in a protein shake?** It varies by product and no UK dataset gives a typical figure. Read the label against the thresholds. A powder is high in sugars at more than 22.5 g per 100 g and low at 5 g or less. A ready-to-drink shake is high at more than 11.25 g per 100 ml and low at 2.5 g or less. **Can you replace meals with protein shakes to lose weight?** A protein shake is not a meal replacement unless it meets the Regulation's conditions on energy, protein, vitamins and minerals. The authorised meal-replacement claims apply only to products that comply. NICE describes diets under 1,200 kcal a day only within specialist services for no more than 12 weeks with dietitian support. It also advises against restrictive diets that are nutritionally unbalanced. HeMed provides clinician-led weight management. This page is general health information, not medical advice. If you are worried about symptoms, speak to your GP, or use NHS 111. Next step: see what the HeMed blood test measures. Sources (22) - British Dietetic Association, Food Fact Sheet "Sport and exercise nutrition", May 2026 (review date May 2029). bda.uk.com/resource/sport-exercise-nutrition.html. Accessed 14 October 2026. - Wirunsawanya K and colleagues. Systematic review and meta-analysis of whey protein supplementation in adults who are overweight or obese. Journal of the American College of Nutrition 2018;37(1):60 to 70. Abstract only. pubmed.ncbi.nlm.nih.gov/29087242. Accessed 14 October 2026. - Food Standards Agency, "Food supplements: guidance for consumers", published 25 June 2026. gov.uk/government/publications/food-supplements-guidance-for-consumers. Accessed 14 October 2026. - Public Health England, McCance and Widdowson's The Composition of Foods Integrated Dataset 2021 (CoFID 2021), file McCance_Widdowsons_Composition_of_Foods_Integrated_Dataset_2021..xlsx, sheet 1.3 Proximates; published 25 March 2015, dataset updated 19 March 2021. Food codes used: 18-323 chicken, breast, grilled without skin, meat only; 16-416 tuna, canned in brine, drained; 12-940 eggs, chicken, whole, boiled; 13-658 lentils, red, split, dried, boiled in unsalted water. The dataset has no entry for whey or any protein powder. gov.uk/government/publications/composition-of-foods-integrated-dataset-cofid. Accessed 14 October 2026. - Department of Health and Social Care, Great Britain nutrition and health claims (NHC) register, spreadsheet dated 19 May 2026: protein health claims, meal replacement for weight control claims, and non-authorised entry 616. gov.uk/government/publications/great-britain-nutrition-and-health-claims-nhc-register. 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Accessed 14 October 2026. - Almiron-Roig E and colleagues. Systematic review of preload studies and energy compensation. Nutrition Reviews 2013;71(7):458 to 473. Abstract only. pubmed.ncbi.nlm.nih.gov/23815144. Accessed 14 October 2026. - Leidy HJ and colleagues. Review of the role of protein in weight loss and maintenance. American Journal of Clinical Nutrition 2015;101(6):1320S to 1329S. Abstract only. doi.org/10.3945/ajcn.114.084038. Accessed 14 October 2026. - Astbury NM and colleagues. The DROPLET randomised controlled trial of total diet replacement in primary care. BMJ 2018;362:k3760. Abstract and competing interests statement only. pubmed.ncbi.nlm.nih.gov/30257983. Accessed 14 October 2026. - NHS, "Food labels", Live Well, page last reviewed 30 June 2026. nhs.uk/live-well/eat-well/food-guidelines-and-food-labels/how-to-read-food-labels. Accessed 14 October 2026. - Department of Health and Food Standards Agency, "Guide to creating a front of pack (FoP) nutrition label for pre-packed products sold through retail outlets", updated November 2016: step 3.1, table 2 and table 3. gov.uk/government/publications/front-of-pack-nutrition-labelling-guidance. Accessed 14 October 2026. - British Dietetic Association, Food Fact Sheet "Supplements", May 2022 (review date May 2025, marked as under review). bda.uk.com/resource/supplements.html. Accessed 14 October 2026. - Scientific Advisory Committee on Nutrition, "Statement on nutrition and older adults living in the community", January 2021, paragraphs 4.22 to 4.24. gov.uk/government/publications/sacn-statement-on-nutrition-and-older-adults. Accessed 14 October 2026. - Public Health England, "Government Dietary Recommendations", 2016, table 2 (protein, males aged 19 to 64). assets.publishing.service.gov.uk, government_dietary_recommendations.pdf. Accessed 14 October 2026. - British Nutrition Foundation, portion size guide: "Find your balance" booklet (January 2019) and "Your balanced diet" full portion size list (November 2021). Portions used: chicken breast grilled 120 g; canned tuna 120 g; eggs (2) 120 g; lentils, beans and other pulses 120 g. nutrition.org.uk/creating-a-healthy-diet/portion-sizes. Accessed 14 October 2026. - NHS, "Eating a balanced diet", Live Well, page last reviewed 30 June 2026. nhs.uk/live-well/eat-well/how-to-eat-a-balanced-diet/eating-a-balanced-diet. Accessed 14 October 2026. - NHS Better Health, "Healthy eating when trying to lose weight". nhs.uk/better-health/lose-weight/healthy-eating-when-trying-to-lose-weight. Accessed 14 October 2026. - Devries MC and colleagues. Meta-analysis of higher protein intake and kidney function in adults without kidney disease. Journal of Nutrition 2018;148(11):1760 to 1775. Abstract only. doi.org/10.1093/jn/nxy197. Accessed 14 October 2026. - University Hospitals Sussex NHS Foundation Trust, patient leaflet "Dietary protein intake for chronic kidney disease", reviewed 11 November 2024. A local trust leaflet, not national NHS guidance. uhsussex.nhs.uk/resources/dietary-protein-intake-for-chronic-kidney-disease. Accessed 14 October 2026. Numbered markers in the page text link to these entries. Statistics describe populations, not any one person’s results. --- This is the plain-text version of the article at https://www.hemed.com/blog/protein-shakes-for-weight-loss, generated from the page on 2026-10-14. It is for information only and is not medical advice. Whether any treatment is right for a person is a clinical decision. Statistics describe populations, not any one person's results.